All-optical Quantum State Engineering for Rotation-symmetric Bosonic States

TL;DR

This paper proposes a practical method for generating non-Gaussian quantum states using optical techniques, crucial for advancing fault-tolerant quantum computing with continuous variables.

Contribution

It introduces a novel approach combining photon subtraction and measurements to produce rotation-symmetric states for quantum error correction.

Findings

Method effectively generates non-Gaussian states with current technology.

Analysis includes effects of experimental imperfections like losses.

Suitable for implementation in existing quantum photonic setups.

Abstract

Continuous-variable quantum information processing through quantum optics offers a promising platform for building the next generation of scalable fault-tolerant information processors. To achieve quantum computational advantages and fault tolerance, non-Gaussian resources are essential. In this work, we propose and analyze a method to generate a variety of non-Gaussian states using coherent photon subtraction from a two-mode squeezed state followed by photon-number-resolving measurements. The proposed method offers a promising way to generate rotation-symmetric states conventionally used for quantum error correction with binomial codes and truncated Schr\"{o}dinger cat codes. We consider the deleterious effects of experimental imperfections such as detection inefficiencies and losses in the state engineering protocol. Our method can be readily implemented with current quantum photonic technologies.